U.S. patent application number 13/289838 was filed with the patent office on 2012-05-10 for process for the preparation of a supramolecular polymer.
This patent application is currently assigned to SupraPolix B.V.. Invention is credited to Anton Willem BOSMAN, Henricus Marie JANSSEN, Gaby Maria Leonarda VAN GEMERT.
Application Number | 20120116014 13/289838 |
Document ID | / |
Family ID | 45023615 |
Filed Date | 2012-05-10 |
United States Patent
Application |
20120116014 |
Kind Code |
A1 |
JANSSEN; Henricus Marie ; et
al. |
May 10, 2012 |
PROCESS FOR THE PREPARATION OF A SUPRAMOLECULAR POLYMER
Abstract
The invention relates to a process for the preparation of a
supramolecular polymer comprising 1-50 4H-units, in which a 4H
building block is reacted with a prepolymer, wherein a 4H building
block comprises a 4H-unit and a reactive group according to Formula
(I): wherein 4H represents a 4H-unit, L represents a divalent,
trivalent, tetravalent or pentavalent linking group, F.sub.i
represents a reactive group, and r is 1-4, is reacted with a
pre-polymer comprising a complementary reactive group, wherein the
reaction mixture comprising said 4H building block and said polymer
comprises less than 10 wt. % of a non-reactive organic solvent,
based on the total weight of the reaction mixture.
Inventors: |
JANSSEN; Henricus Marie;
(Eindhoven, NL) ; VAN GEMERT; Gaby Maria Leonarda;
(Roermond, NL) ; BOSMAN; Anton Willem; (Eindhoven,
NL) |
Assignee: |
SupraPolix B.V.
|
Family ID: |
45023615 |
Appl. No.: |
13/289838 |
Filed: |
November 4, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61410410 |
Nov 5, 2010 |
|
|
|
Current U.S.
Class: |
524/590 ;
525/123; 528/73 |
Current CPC
Class: |
C08G 18/3246 20130101;
C08G 83/008 20130101; C08G 18/807 20130101 |
Class at
Publication: |
524/590 ; 528/73;
525/123 |
International
Class: |
C08G 18/78 20060101
C08G018/78; C09J 175/12 20060101 C09J175/12; C09D 175/12 20060101
C09D175/12 |
Claims
1. A process for the preparation of a supramolecular polymer
comprising about 1-50 4H-units, the process comprising reacting a
4H building block comprising a reactive group with a prepolymer
comprising a complementary reactive group in a reaction mixture
comprising less than 10 wt. % of a non-reactive organic solvent,
based on the total weight of the reaction mixture, wherein the 4H
building block is formulated as a liquid at a temperature lower
than about 100.degree. C. and comprises a 4H-unit and a reactive
group according to Formula (I): 4H-(L-F.sub.i).sub.r (I) wherein 4H
represents a 4H-unit; L represents a divalent, trivalent,
tetravalent or pentavalent linking group; F.sub.i represents a
reactive group; and r is 1-4.
2. The process according to claim 1, wherein the reacting is
performed at a temperature between about 10.degree. C. and about
100.degree. C.
3. The process according to claim 1, wherein L is a divalent
linking group.
4. The process according to claim 3, wherein the 4H building block
is represented by: 4H-L-F.sub.1 or F.sub.1-L--4H-L-F.sub.1 or
F.sub.1-L-4H-L-F.sub.2 wherein F.sub.1 and F.sub.2 are independent
reactive groups.
5. The process according to claim 4, wherein L is a linear,
branched or cyclic C.sub.1-C.sub.20 alkylene group, a
C.sub.6-C.sub.20 arylene group, a C.sub.7-C.sub.20 arylalkylene or
a C.sub.7-C.sub.20 alkylarylene group, wherein the alkylene group,
the arylene group, the arylalkylene group and the alkylarylene
group are optionally substituted and/or are optionally interrupted
by 1-4 atoms selected form the group consisting of O, N, and S, or
by 1-4 groups selected from the group consisting of ureido,
urethane, uretdione, isocyanurate, and ester.
6. The process according to claim 1, wherein L is a polymeric group
having a molecular weight between 500 and 5000 Da.
7. The process according to claim 6, wherein L is a linking group
having a glass transition temperature below 0.degree. C.
8. The process according to claim 7, wherein L is selected from the
group consisting of aliphatic polyethers, aliphatic polyesters,
aliphatic polycarbonates, polyorthoesters, polysiloxanes,
(hydrogenated) polybutadienes, and poly(meth)acrylates.
9. The process according to claim 1, wherein the reaction mixture
comprises a chain extender according to formula (II): Z(-G).sub.n
(II) wherein n=2 to 5; Z is a C.sub.2-C.sub.24 alkylene group, a
C.sub.6-C.sub.24 arylene group, a C.sub.7-C.sub.24 alkylarylene
group or a C.sub.7-C.sub.24 arylalkylene group, optionally
interrupted by 1 to 6 hetero atoms selected form N, O and S; and G
represents --OH and/or -NH.sub.2.
10. The process according to claim 1, wherein the 4H-unit is
according to Formula (III) or Formula (IV): ##STR00007## wherein X
is a nitrogen atom or a carbon atom bearing a substituent R.sup.8,
and wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.8 are independently
selected from the group consisting of hydrogen, C.sub.1-C.sub.20
alkyl, C.sub.6-C.sub.12 aryl, C.sub.7-C.sub.12 alkaryl, and
C.sub.7-C.sub.12 alkylaryl, or wherein R.sup.1, R.sup.2 and R.sup.3
are independently a direct bond.
11. The process according to claim 10, wherein X is a nitrogen
atom.
12. The process according to claim 10, wherein the 4H-unit is
represented by Formula (III).
13. The process according to claim 12, wherein R.sup.2 and R.sup.3
are independently selected from the group consisting of hydrogen,
C.sub.1-C.sub.20 alkyl, C.sub.6-C.sub.12 aryl, C.sub.7-C.sub.12
arylalkyl, and C.sub.7-C.sub.12 alkylaryl and the 4H building block
is represented by Formula (IIIa).
14. The process according to claim 12, wherein R.sup.2 is selected
from the group consisting of hydrogen, C.sub.1-C.sub.20 alkyl,
C.sub.6-C.sub.12 aryl, C.sub.7-C.sub.12 arylalkyl, and
C.sub.7-C.sub.12 alkylaryl and the 4H building block is represented
by Formula (IIIc).
15. The process according to claim 13, wherein R.sup.2 is
methyl.
16. The process according to claim 14, wherein R.sup.2 is
methyl.
17. The process according to claim 1, wherein the reaction mixture
comprises a liquid polyisocyanate, a liquid polyol, a liquid
polyamino-alcohol, or a liquid polyamine, each having has a dynamic
viscosity at 22.degree. C. of about 0.1 to about 5 Pas and/or a
number average molecular weight of about 56 to about 500
Dalton.
18. The process according to claim 17, wherein the molar ratio of
the 4H building block to liquid polyisocyanate, liquid polyol,
liquid polyamino-alcohol, or liquid polyamine is between about 1 to
about 3-10.
19. The process according to claim 18, wherein the liquid
polyisocyanate is selected from the group consisiting of isophorone
diisocyanate, methylene dicyclohexane 4,4-diisocyanate, methylene
diphenyl diisocyanate, uretdione dimer of hexane diisocyanate,
1,6-diisocyanato-2,2,4-trimethylhexane, and
1,6-diisocyanato-2,4,4-trimethylhexane.
20. The process according to claim 1, wherein no organic solvent is
present in the reaction mixture.
21. The process according to claim 1, wherein no solvent is present
in the reaction mixture.
22. A coating composition comprising the supramolecular polymer
obtained by the process according to claim 1.
23. An adhesive composition comprising the supramolecular polymer
obtained by the process according to claim 1.
Description
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
[0001] This application claims priority from U.S. Provisional
Application No. 61/410,410, filed Nov. 5, 2010, incorporated herein
by reference in its entirety.
FIELD OF THE INVENTION
[0002] The invention relates to a process for the preparation of a
supramolecular polymer comprising a quadruple hydrogen bonding unit
(abbreviated herein as "4H-unit") wherein a 4H-unit comprising a
reactive group is reacted with a pre-polymer comprising a
complementary reactive group, wherein the reaction mixture
comprising said 4H-unit and said polymer comprises less than 10 wt.
% of an organic solvent. The reaction is preferably performed at
temperatures below about 100.degree. C. The resulting
supramolecular polymer shows unique new characteristics due to the
presence of additional physical interactions between the polymer
chains that are based on multiple hydrogen bonding interactions
(supramolecular interactions) and benefit from easier and faster
preparation and handling using known reactive-processing
techniques.
BACKGROUND OF THE INVENTION
[0003] This invention relates to a process for the preparation of a
supramolecular polymer comprising a 4H-unit that is capable of
forming at least four H-bridges in a row, preferably with another
4H-unit, leading to physical interactions between different polymer
chains. The physical interactions originate from multiple hydrogen
bonding interactions (supramolecular interactions) between
individual 4H-units or between a 4H-unit and another moiety capable
of forming hydrogen bonds thereby forming self-complementary units,
preferably comprising at least four hydrogen bonds in a row. Units
capable of forming at least four hydrogen bonds in a row, i.e.
quadruple hydrogen bonding units, are in this patent application
abbreviated as "4H-units". Sijbesma et al. (U.S. Pat. No.
6.320.018; Science 278, 1601-1604, 1997; both incorporated by
reference herein) discloses 4H-units that are based on
2-ureido-4-pyrimidones. These 2-ureido-4-pyrimidones in their turn
are derived from isocytosines.
[0004] Telechelic polymers or trifunctional polymers have been
modified with 4H-units (Folmer, B. J. B. et al., Adv. Mater. 12,
874-878, 2000; Hirschberg et al., Macromolecules 32, 2696-2705,
1999; Lange, R. F. M. et al, J. Polym. Sci. Part A, 37, 3657-3670,
1999; all incorporated by reference). However, these polymers are
obtained by addition of solid reactants to chloroform or toluene
solutions, which are both toxic organic solvents, and need
prolonged reaction times of several hours in order to reach
completion.
[0005] US 2004/087755, incorporated by reference, discloses
polyurethane based polymers with 4H-units as end-cappers that can
be used as hot melt adhesive. Example 4 in this patent discloses
the preparation of supramolecular polyurethane polymers which are
obtained by the bulk reaction of 6-methyl-isocytosine with
4,4'-methylene bis(phenyl isocyanate) (MDI) end-capped polyesters
in the melt at 180.degree. C., said reaction being performed in a
Brabender mixer with a residence time of not more than 3 minutes.
In this process it is preferred that the 6-methyl-isocytosine is
added as a powder that is finely milled to a particular particle
size to facilitate rapid and efficient conversion.
[0006] JP 2004250623, incorporated by reference, discloses
polyester diols derived from poly(butanediol terephthalate) or
polylactide that are reacted in the melt with a solid reactant
comprising isocyanato functional 4H-unit, obtained by the reaction
of a diisocyanate with 6-methyl-isocytosine. The reaction proceeds
by kneading at 150.degree. C. to 300.degree. C., preferably at
160.degree. C. to 250.degree. C. and more preferably at 180.degree.
C. to 230.degree. C. JP 2004250623 further discloses that it is
desirable to perform the reaction above the melting point of the
polymer. However, in order to control decomposition of the
reactants and final products, the reaction is desirably performed
at a temperature as low as possible, provided that the reactants
are prevented to solidify as much as possible during the reaction.
According to the examples, the reaction requires temperatures of
200.degree. C. or higher and an excess of the isocyanato functional
4H-unit. Comparable functionalization of poly(butanediol
terephthalate) and poly(butanediol isophthalate) with this
isocyanato functional 4H-unit at temperatures above 180.degree. C.
are also disclosed by Yamauchi et al. (Macromolecules 37,
3519-3522, 2004; incorporated by reference). In both cases the
excess of the 4H-unit in the synthesis has been removed using
organic solvents (Soxhlet-extraction with methanol or precipitation
from HFIP), thereby re-introducing the need of (toxic) organic
solvents into the process. Moreover, the occurrence of side
reactions with the isocyanate functional compound, like
allophonate, biuret or isocyanurate formation, is eminent at the
temperatures applied as is well known in the art (High Polymers
Vol. XVI, Polyurethanes: chemistry and technology, Part 1, Ed.: J.
B. Saunders and K. C. Frisch; J. Wiley & Sons, 1962;
incorporated by reference).
[0007] Additionally, US 2010/0076147, incorporated by reference,
discloses supramolecular polymers comprising 4H-units which are
obtained by reactive extrusion in the melt at temperatures below
150.degree. C. In order to be able to perform the melt processing,
the 4H-units have been modified with e.g. C.sub.2-C.sub.20 alkyl
chains on the heterocyclic ring structure in order to lower their
melting point. Therefore, only specific, synthetically demanding,
4H-units can be used in this approach. Moreover, the 4H-unit is a
powder at handling temperatures and needs relatively high
processing temperatures (Examples 15-18 disclose reaction
temperatures of 120.degree. C. to 140.degree. C. for the conversion
into a supramolecular polymer.
[0008] Clearly, there is a need in the art for a process for the
preparation of a supramolecular polymer containing a 4H-unit that
does not require one or more organic solvents because of
toxicological, ecological and economical reasons. Moreover, there
is a need in the art for a bulk process that can be performed at
temperatures below about 100.degree. C. in which the different
ingredients are formulated as liquids and can be dosed using known
liquid-handling techniques in the art. There is also a need in the
art for a broad range of liquid formulations comprising reactive
4H-units thereby facilitating essentially solvent-free processing
of liquid reactants at moderate temperatures.
SUMMARY OF THE INVENTION
[0009] The present invention discloses a process for the
preparation of a supramolecular polymer comprising 1-50 4H-units,
in which a 4H building block is reacted with a prepolymer, wherein
a 4H building block comprising a 4H-unit and a reactive group
according to Formula (I):
4H-(L-F.sub.i).sub.r (I)
wherein 4H represents a 4H-unit, L represents a divalent,
trivalent, tetravalent or pentavalent linking group, F.sub.i
represents a reactive group, and r is 1-4, is reacted with a
pre-polymer comprising a complementary reactive group, wherein the
reaction mixture comprising said 4H building block and said polymer
comprises less than 10 wt. % of a non-reactive organic solvent,
based on the total weight of the reaction mixture.
DETAILED DESCRIPTION OF THE INVENTION
[0010] The verb "to comprise" as is used in this description and in
the claims and its conjugations is used in its non-limiting sense
to mean that items following the word are included, but items not
specifically mentioned are not excluded. In addition, reference to
an element by the indefinite article "a" or "an" does not exclude
the possibility that more than one of the element is present,
unless the context clearly requires that there is one and only one
of the elements. The indefinite article "a" or "an" thus usually
means "at least one".
[0011] (Self)-complementary units capable of forming at least four
hydrogen bonds form in principle non-covalent moieties with each
other. However, it is within the scope of this invention that these
units can form non-covalent moieties with other materials capable
of forming less than four hydrogen bonds. The hydrogen bonding
sites comprising one Bonding Unit can form a non-self-complementary
or a self-complementary binding group. Non-self-complementary means
that a 4H-unit A forms a bonding moiety A-B with a unit B, wherein
B is a different 4H-unit. Self-complementary means that two
4H-units A form a bonding moiety A-A. It is preferred that the
4H-unit is self-complementary.
[0012] The term "(self)-complementary units capable of forming four
hydrogen bonds in a row is used in its abbreviated form "4H-unit".
Hence, a "supramolecular polymer comprising a (self-)complementary
unit capable of forming at least four hydrogen bonds in a row" is
in this document alternatively indicated as a "supramolecular
polymer comprising a 4H-unit". The 4H-unit is covalently attached
to or covalently incorporated in the polymer chain.
[0013] A liquid means a fluid that has a kinematic viscosity of
about 2 to about 2000 cSt at a temperature of about 20.degree. C.
to about 100.degree. C.
[0014] A solvent means a liquid that is present during a (reactive)
processing step but that is not significantly consumed or modified
during said processing step and hence needs to be removed after
processing to obtain the product.
[0015] It was unexpectedly found that 4H-units comprising a
reactive group (i.e., a 4H building block) could be formulated in
reactive solvents such as liquid (di)isocyanates, liquid polyols,
liquid polyamino-alcohols and/or liquid polyamines or could be
obtained in a liquid form as such. In this way, the 4H-units can be
handled as a liquid during manufacturing allowing the use of closed
systems, pumping, pouring etc., and excluding the need for
expensive and cumbersome powder handling techniques and/or the
presence of (organic) solvents. This results in supramolecular
polymers containing one or more 4H-units with excellent mechanical
properties. The process according to the present invention leads
therefore to a large improvement in the production and use of these
supramolecular polymers since it makes the use of solid,
crystalline ingredients and/or reaction temperatures above
140.degree. C. obsolete.
[0016] The 4H building block
[0017] The 4H building block used in the process for the
preparation of supramolecular polymers of the present invention is
represented by Formula (I),
4H-(L-F.sub.i).sub.r (I)
wherein: [0018] 4H represents a 4H-unit; [0019] L represents a
divalent, trivalent, tetravalent or pentavalent linking group,
F.sub.i represents a reactive group, and r is 1-4. [0020] Hence,
the 4H-unit may comprise up to four reactive groups F.sub.1,
F.sub.2, F.sub.3 and F.sub.4.
[0021] According to the present invention, r can be from 1 to 4.
According to the present invention, r is preferably 1 or 2 and most
preferably 2.
[0022] According to the present invention, the 4H-unit is
preferably (r=1 or 2) represented by the following formulae:
4H-L-F.sub.1 or F.sub.1--L-4H-L-F.sub.1 or
F.sub.1--L-4H--L-F.sub.2
wherein F.sub.1 and F.sub.2 are independent reactive groups, i.e.
F.sub.1 may be different from or the same as F.sub.2.
[0023] According to an embodiment, L is a linear, branched or
cyclic C.sub.1-C.sub.20 alkylene group, a C.sub.6-C.sub.20 arylene
group, a C.sub.7-C.sub.20 arylalkylene group or a C.sub.7-C.sub.20
alkylarylene group, wherein the alkylene group, the arylene group,
the arylalkylene group and the alkylarylene group are optionally
interrupted by 1-4 atoms selected form the group consisting of O,
N, and S.
[0024] According to another embodiment, the alkylene group, the
arylene group, the arylalkylene group and the alkylarylene group
are optionally interrupted by 1-4 groups selected from the group
consisting of ureido, urethane, uretdione, isocyanurate, and
ester.
[0025] According to yet another embodiment, L comprises a polymeric
group having a molecular weight in between 500 and 5000 Da and has
preferably a glass transition temperature about below 0.degree. C.
In this embodiment, L is preferably selected from the group
consisting of aliphatic polyethers, aliphatic polyesters, aliphatic
polycarbonates, polyorthoesters, polysiloxanes, (hydrogenated)
polybutadienes, and poly(meth)acrylates, optionally comprising end
groups selected from linear, branched or cyclic C.sub.1-C.sub.20
alkylene groups, C.sub.6-C.sub.20 arylene groups, C.sub.7-C.sub.20
arylalkylene groups, and C.sub.7-C.sub.20 alkylarylene groups.
[0026] In general, the structural element that is capable of
forming at least four hydrogen bridges (4H) has the general form
(1) or (2):
##STR00001##
wherein the C--X, and the C--Y, linkages each represent a single or
double bond, n is 4 or more, and X.sub.i represent donors or
acceptors that form hydrogen bridges with the H-bridge forming
monomeric unit containing a corresponding general form (2) linked
to them with X.sub.i representing a donor and Y.sub.i an acceptor
and vice versa. The structure of these 4H-units is in detail
disclosed in U.S. Pat. No. 6,320,018 which is expressly
incorporated by reference.
[0027] It is preferred that in formulas (1) and (2) n equals 4 so
and that the 4H-unit comprises four donors or acceptors in the
arrays X.sub.1 . . . X.sub.4 and The 4H-unit may be
self-complementary (i.e. the two hydrogen bonded units have an
equal array of donors and acceptors), or non self-complementary
(i.e. the two hydrogen bonded units have two different arrays of
donors and acceptors). Preferably, the 4H-unit comprises two
successive donors, followed by two successive acceptors, i.e. it is
preferred that X.sub.1 and X.sub.2 are donors and X.sub.3 and
X.sub.4 are acceptors. Preferably, the donors and acceptors are O,
S, and N atoms.
[0028] According to yet another embodiment of the present invention
the 4H-unit has the general Formula (III) or Formula (IV), and
tautomers thereof:
##STR00002##
wherein X is a nitrogen atom or a carbon atom bearing a substituent
R.sup.8, preferably a nitrogen atom, and wherein R.sup.1, R.sup.2,
R.sup.3 and R.sup.8 are independently selected from the group
consisting of: [0029] (a) hydrogen; [0030] (b) C.sub.1-C.sub.20
alkyl; [0031] (c) C.sub.6-C.sub.12 aryl; [0032] (d)
C.sub.7-C.sub.12 alkaryl; [0033] (e) C.sub.7-C.sub.12 alkylaryl.
R.sup.1, R.sup.2 and R.sup.3 may also be a direct bond.
[0034] In a first preferred embodiment, the 4H-unit is bonded to
linker L via R.sup.1 (so that R.sup.1 is absent and r=1), while
R.sup.2, R.sup.3 and R.sup.8 are independently any one of the
groups (a)-(e) defined above, preferably group (a) and (b). Hence,
according to this first preferred embodiment, the 4H building block
is then represented by:
##STR00003##
[0035] Even more preferably, R.sup.2, R.sup.3 and R.sup.8 are
independently selected from hydrogen, methyl, ethyl, n-butyl or
t-butyl. Most preferably, R.sup.2 is methyl and R.sup.3 is
hydrogen.
[0036] In a second preferred embodiment, the 4H-unit is bonded to
linker L via R.sup.1 and R.sup.2 (so that R.sup.1 and R.sup.2 are
both absent and r=2), while R.sup.3 and R.sup.8 are selected from
any one of the groups (a)-(e) defined above, more preferably from
group (a) and (b), most preferably from group (a). Hence, according
to this first preferred embodiment, the 4H building block is then
represented by:
##STR00004##
[0037] In a third preferred embodiment, the 4H-unit is bonded to
linker L via R.sup.1 and R.sup.3 (so that R.sup.1 and R.sup.3 are
absent and r=2), while R.sup.2 and R.sup.8 are selected from any
one of the groups (a)-(e) defined above, preferably group (b). Even
more preferably, R.sup.2 is independently selected from methyl,
ethyl, n-butyl or t-butyl, most preferably R.sup.2 is methyl.
Hence, according to this first preferred embodiment, the 4H
building block is then represented by:
##STR00005##
[0038] This first and third preferred embodiments are more
preferred than the second preferred embodiment, the third preferred
embodiment is most preferred.
[0039] As will be apparent to the person skilled in the art, the
groups (b)-(e) defined above may be linear, branched or cyclic
where appropriate.
[0040] In this document, the terms "reactive group" and
"complementary reactive group" are used interchangeably to indicate
reactive groups that are capable to form a bond, preferably a
covalent bond, with each other under conventional reaction
conditions as will be apparent to a person skilled in the art.
Preferably, the reactive groups and complementary reactive groups
are selected such that they form a linking group selected from:
[0041] --C(O)--O--; [0042] --O--; [0043] --C(O)--N--; [0044]
--N(H)--C(O)--O--; and [0045] --N(H)--C(O)--N(H)--; [0046]
Preferred examples of pairs of reactive groups and complementary
reactive groups are: [0047] carboxylic acid groups/hydroxy groups
that can form an ester group --C(O)--O--; [0048] carboxylic acid
groups/amine groups that can form an amide group --C(O)--N--;
[0049] hydroxy groups/hydroxy groups that can form an ether group
--O--; [0050] isocyanate groups/hydroxyl groups than can form a
carbamate group --N(H)--C(O)--O--; [0051] isocyanate groups/amine
groups than can form an ureido group --N(H)--C(O)--N(H)--.
[0052] Instead of a carboxylic acid group, a carboxylic ester or
carboxylic acid halide group may be used. Instead of an isocyanate
group, a thioisocyante group can be used. Instead of a hydroxyl
group, a thiol group may be used. As amine group, a primary,
secondary or tertiary amine group may be used (although primary
amine groups are preferred). The carboxylic ester group may be
activated. The (thio)isocyanate group may be blocked. In this
document, "hydroxy" denotes a --OH group.
[0053] A "carboxylic acid group" denotes a --C(O)OH group.
[0054] A "carboxylic ester group" denotes a --C(O)OR group, wherein
R is selected from the group consisting of C.sub.1-C.sub.6 alkyl,
C.sub.6-C.sub.12 aryl, C.sub.7-C.sub.12 arylalkyl and
C.sub.7-C.sub.12 alkylaryl groups, wherein the alkyl groups may be
linear, branched or cyclic. Arylalkyl groups are groups such as
phenylmethyl while alkylaryl groups are groups like
4-methylphenyl.
[0055] An "carboxylic acid halide group" denotes a --C(O)X group,
wherein X is a chlorine atom, a bromine atom or a iodine atom.
Preferably X is a chlorine or a bromine atom.
[0056] An "isocyanate" denotes a --NCO group.
[0057] A "blocked isocyanate" denotes a --NHC(O)OR* group, wherein
R* is a good leaving group. Suitable examples of good leaving
groups are phenol-derivatives phenol and thiophenol derivatives,
ester derivatives such as the methyl ester of hydroxy-benzoic acid,
alcohol derivatives such as 2-ethyl-hexyl-alcohol and
t-butyl-alcohol, oxime derivatives such as methyl-ethyl ketoxime,
imidazole groups, caprolactam groups and hydroxy-succinimide
groups.
[0058] A "thioisocyanate group" denotes a --NCS group.
[0059] An "blocked thioisocyanate group" denotes a --NHC(S)OR*
group, wherein R* is a good leaving group as indicated for "blocked
isocyanate".
[0060] A "primary amine group" denotes a --NH.sub.2 group.
[0061] A "secondary amine group" denotes a --NHR group, wherein R
is selected from the group consisting of C.sub.1-C.sub.6 alkyl,
C.sub.6-C.sub.12 aryl, C.sub.7-C.sub.12 alkylaryl and
C.sub.7-C.sub.12 arylalkyl groups, wherein the alkyl groups may be
linear, branched or cyclic.
[0062] An "activated amine" denotes a --C(R).dbd.NOH group (that
can be converted into an amine group via the Beckmann
rearrangement), a --C(O)N.sub.3 group (that can be converted into
an amine group via the Curtius rearrangement), a --C(O)NH.sub.2
group (that can be converted into an amine group via the Hofmann
rearrangement), a --NHC(O)R group wherein R is selected from the
group consisting of C.sub.1-C.sub.6 alkyl, C.sub.6-C.sub.12 aryl,
C.sub.7-C.sub.12 alkylaryl and C.sub.7-C.sub.12 arylalkyl groups,
wherein the alkyl groups may be linear, branched or cyclic
including cyclic groups such as caprolactamyl
(1-aza-2-cycloheptanon-1yl), a heterocyclic five or six membered
group comprising 3-12 carbon atoms and 1-3 heteroatoms selected
from the group consisting of O, S and N such as imidazole.
According to the present invention, the "activated amine group" is
preferably caprolactamyl (1-aza-2-cycloheptanon-1yl) or an
1-imidazolyl group.
[0063] A "thiol" denotes a --SH group.
[0064] A "halogen" denotes a --X group, where X is chlorine,
bromine or iodine.
Formulation of the 4H Building Block
[0065] The 4H building block used in the process for the
preparation of supramolecular polymers of the present invention is
preferably formulated as a liquid at temperatures lower than about
100.degree. C.
[0066] The liquid formulation comprising the 4H building block has
preferably a kinematic viscosity of about 20 to 2000 cSt at about
100.degree. C., preferably at about 90.degree. C., more preferably
at about 80.degree. C., most preferably at about 40.degree. C.
[0067] In a first, preferred, embodiment of this invention the
liquid formulation comprises a 4H building block and a reactive
solvent. Preferably, part of the reactive solvent is consumed in
the synthesis of the 4H building block such that the formulation is
directly obtained upon preparation of the 4H building block (a
`one-pot` process).
[0068] In a second embodiment of this invention, the liquid
formulation of a 4H building block comprises a 4H building block
according to formula (I), in which L is a polymer.
[0069] In said first preferred embodiment, the liquid formulation
of the 4H building block is obtained by i) using an excess of a
liquid polyisocyanate, or ii) using an excess of a liquid polyol, a
liquid polyamino-alcohol, or a liquid polyamine. Alternatively, the
4H building block, the liquid polyisocyanate, the liquid polyol,
the liquid polyamino-alcohol, or the liquid polyamine, and the
pre-polymer may be mixed to form a reaction mixture. Preferably,
the liquid polyisocyanate, the liquid polyol, the liquid
polyamino-alcohol, or the liquid polyamine have preferably a
dynamic viscosity at 22.degree. C. of about 0.1 to about 5 Pas
and/or a number average molecular weight of about 56 to about 500
Dalton. Preferably, the molar ratio of the 4H building block to the
liquid polyisocyanate, the liquid polyol, the liquid
polyamino-alcohol, or the liquid polyamine is between about 1 to
about 3-10, preferably about 1 to about 3-6.
[0070] In the first preferred method i) of the first preferred
embodiment, an isocytosine-derivative according to formula (5) or a
melamine-derivative according to formula (6) (and/or tautomers
thereof), with X, R.sup.2 and R.sup.3 as defined above, preferably
an isocytosine, is reacted with a polyisocyanate having preferably
a dynamic viscosity at 22.degree. C. of about 0.1 to about 5 Pas,
The molar ratio of the 4H building block to the liquid
polyisocyanate is preferably between about 1 to about 3-10,
preferably about 1 to about 3-6, to form a 4H building block
according to formula (I) with F.sub.i.dbd.NCO formulated in a
polyisocyanate.
##STR00006##
[0071] The polyisocyanate has an average isocyanate-functionality
of 1.5 to 5, preferably 2 to 3, most preferably 2, according to
formula Y(--NCO).sub.n with n=1.5 to 5, wherein Y represents a
C.sub.2-C.sub.24 alkylene group, a C.sub.6-C.sub.24 arylene group,
a C.sub.7-C.sub.24 alkylarylene group or a C.sub.7-C.sub.24
arylalkylene group, optionally interrupted by 1 to 6 hetero atoms
selected form N, O and S. The polyisocyanate may include biuret,
urethane, uretdione, and isocyanurate derivatives. The
polyisocyanate Y(--NCO).sub.n is preferably selected from the group
consisting of toluene diisocyanate (TDI), methylene diphenyl
diisocyanate (MDI), methylene dicyclohexane 4,4-diisocyanate
(HMDI), isophorone diisocyanate (IPDI), hexane diisocyanate (HDI),
1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, uretdione
dimers of hexane diisocyanate, and cyclic trimers (isocyanurates)
of HDI and IPDI, more preferably from the group consisting of
isophorone diisocyanate, methylene dicyclohexane 4,4-diisocyanate,
methylene diphenyl diisocyanate, uretdione dimer of hexane
diisocyanate, 1,6-diisocyanato-2,2,4-trimethylhexane, and
1,6-diisocyanato-2,4,4-trimethylhexane. Most preferably, the
diisocyanate OCN--Y--NCO is methylene dicyclohexane
4,4-diisocyanate (HMDI), methylene diphenyl diisocyanate, or
uretdione dimer of hexane diisocyanate.
[0072] In the second method ii) of the first preferred embodiment,
a 4H building block comprising an isocyanate according to formula
(I) with F.sub.i.dbd.--NCO, is reacted with an excess of a liquid
polyol, liquid polyamino-alcohol, or liquid polyamine, preferably a
liquid polyol, wherein the liquid polyol, the liquid
polyamino-alcohol, or the liquid polyamine have preferably a
viscosity at 22.degree. C. of 0.1 to 5 Pas and a molecular weight
of about 56 to about 500 Dalton. The molar ratio of the isocyanate
4H-unit to the liquid polyol, the liquid amino-alcohol, or the
liquid polyamine is preferably between about 1 to about 3-10,
preferably about 1 to about 3-6, to form a new 4H building block
according to formula (I) with F.sub.i.dbd.--OH or --NH.sub.2
formulated in a liquid polyol, liquid polyamino-alcohol, or liquid
polyamine. The liquid polyol, liquid polyamino-alcohol, or liquid
polyamine has an average functionality of 1.5 to 5, preferably 2 to
3, most preferably 2, according to Formula (II) Z(-G).sub.n with
n=1.5 to 5, wherein Z is a C.sub.2-C.sub.24 alkylene group, a
C.sub.6-C.sub.24 arylene group, a C.sub.7-C.sub.24 alkylarylene
group or a C.sub.7-C.sub.24 arylalkylene group, optionally
interrupted by 1 to 6 hetero atoms selected form N, O and S; and G
represent --OH and/or --NH.sub.2. Non-limiting examples of diols
are ethylene glycol, diethylene glycol, triethyleneglycol,
1,2-propylene glycol, 1,3-propylene glycol, tetramethylene glycol,
1,5-pentanediol, 1,6-hexandediol, neopenylglycol, and
1,4-butanediol.
[0073] In the second embodiment of this invention an
isocytosine-derivative according to formula (5) or a
melamine-derivative according to formula (6), preferably an
isocytosine derivative, is reacted with an isocyanate functional
prepolymer obtained by the reaction of polymer having two
hydroxy-endgroups with about 2 to 6 molar equivalents of
diisocyanate, preferably with about 2 to 3, and most preferably
with about 2 molar equivalents of diisocyanate to form a functional
4H-unit according to formula (I) with F.sub.i.dbd.NCO. In which the
polymer with two hydroxy endgroups has a glass transition (T.sub.g)
below 50.degree. C., preferably below 20.degree. C., and most
preferably below -20.degree. C., additionally said polymer has no
melt transition (T.sub.m) higher than -20.degree. C. Preferably,
the number average molecular weight of the polymer with two hydroxy
endgroups is in between about 450 and about 4000 Da, more
preferably in between about 500 and about 2500 Da. The
diisocyanates are selected the group consisting of toluene
diisocyanate (TDI), methylene diphenyl diisocyanate (MDI),
methylene dicyclohexane 4,4-diisocyanate (HMDI), isophorone
diisocyanate (IPDI), hexane diisocyanate (HDI), 1,3-xylylene
diisocyanate, 1,4-xylylene diisocyanate, uretdione dimers of HDI,
more preferably from the group consisiting of IPDI, HMDI, MDI, TDI,
1,6-diisocyanato-2,2,4-trimethylhexane, and
1,6-diisocyanato-2,4,4-trimethylhexane. Most preferably, the
diisocyanate is isophorone diisocyanate (IPDI) or methylene
dicyclohexane 4,4-diisocyanate (HMDI).
Preparation of the Supramolecular Polymer
[0074] The present invention relates to a process for the
preparation of a supramolecular polymer using the liquid
formulation of the 4H building block. Preferably, the
supramolecular polymer is a polymer comprising at least two
4H-units. Hence, the supramolecular polymer comprises about 1-50
4H-units, preferably about 1.5-20, more preferably about 2-10, and
most preferably about 3-10 4H-units. The 4H-units are covalently
attached to the polymer chain. The present invention also relates
to a supramolecular polymer obtainable by said process.
[0075] It is preferred that the polymer used to prepare the
supramolecular polymer is a polyol with an average hydroxyl number
in between about 18 to 300, more preferably in between 18 to 150 mg
KOH/g, and hydroxyl functionalities in between 1.5 to 3.5, more
preferably in between 1.8 and 2.2. The polyol further has a
molecular weight in between 500 to 6000, more preferably in between
500 to 2500 Da. Polyols are well known in the art and are
preferably selected from the group consisting of hydroxy-terminated
polyethers (preferably aliphatic polyethers), aliphatic polyesters,
partly aromatic polyesters, aromatic polyesters, polyamides
(preferably aliphatic polyamides; for example polypeptides),
polycarbonates (preferably aliphatic polycarbonates),
polyorthoesters, polysiloxanes, (hydrogenated) polybutadienes, and
poly(meth)acrylates, or mixtures thereof. It is even more preferred
that the supramolecular polymer is selected from the group
consisting of aliphatic polyethers, aliphatic polyesters, partly
aromatic polyesters, aliphatic polyamides, aliphatic
polycarbonates, aliphatic polyorthoesters, or mixtures thereof. It
is most preferred that the supramolecular polymer is selected from
aliphatic polyethers and aliphatic polyesters or mixtures thereof.
In another embodiment of this invention, the supramolecular polymer
comprises a blend of supramolecular polymers, for example blends of
the preferred groups of supramolecular polymers disclosed
above.
[0076] According to a preferred embodiment of the invention, the
supramolecular polymer is selected from the group consisting of
polyethers and copolyethers based on ethylene oxide, propylene
oxide, and/or tetrahydrofuran; polyesters and copolyesters based on
adipic acid, succinic acid, phthalic acid, and diols, preferably
glycols, butanediols or hexanediols; polyesters and copolyesters
based on .epsilon.-caprolactone, glycolide, lactide,
.delta.-valerolactone, 1,4-dioxane-2-one, 1,5-dioxepan-2-one, or
oxepan-2,7-dione; polycarbonates and copolycarbonates based on
1,6-hexanediol polycarbonate; polycarbonates and copolycarbonates
based on trimethylenecarbonate, 1,3-dioxepane-2-one,
1,3-dioxanone-2-one, or
1,3,8,10-tetraoxacyclotetradecane-2,9-dione; or polyorthoesters
based on 3,9-diethylene-2,4,8,10-tetraoxaspiro[5.5]undecane.
[0077] According to the first method in the first preferred
embodiment and to the second preferred embodiment, the
supramolecular polymer is obtainable by the reaction of the
isocyanate 4H-unit with the polyol, optionally in the presence of a
chain extender, in which the different quantities of the different
components depend on the nature of the supramolecular polymer to be
produced and will be easily ascertained by someone skilled in the
art. Preferably, the total amount of hydroxy- and amine-functions
present in said polyol and the optional chain extender, is at least
the amount of non-reacted isocyanate functions in said reaction
mixture.
[0078] According to the second method in the first preferred
embodiment, the supramolecular polymer is obtainable by the
reaction of the 4H-unit with an isocyanate functional polyol,
optionally in the presence of a chain extender, in which the
different quantities of the different components depend on the
nature of the supramolecular polymer to be produced and will be
easily ascertained by someone skilled in the art. Preferably, the
total amount of hydroxy- and amine-functions present in said polyol
and the optional chain extender, is at least the amount of
non-reacted isocyanate functions in said reaction mixture.
[0079] The isocyanate functional polyol is obtainable by the
reaction of a polymer having two hydroxy-endgroups with about 1 to
4 equivalents of diisocyanate per hydroxy-function, preferably with
about 1 to 2, and most preferably with about 1 equivalents of
diisocyanate. The diisocyanates are selected the group consisting
of toluene diisocyanate (TDI), methylene diphenyl diisocyanate
(MDI), methylene dicyclohexane 4,4-diisocyanate (HMDI), isophorone
diisocyanate (IPDI), hexane diisocyanate (HDI), 1,3-xylylene
diisocyanate, 1,4-xylylene diisocyanate, uretdione dimers of HDI,
more preferably from the group consisiting of IPDI, HMDI, MDI, TDI,
1,6-diisocyanato-2,2,4-trimethylhexane, and
1,6-diisocyanato-2,4,4-trimethylhexane. Most preferably, the
diisocyanate is isophorone diisocyanate (IPDI) or methylene
dicyclohexane 4,4-diisocyanate (HMDI).
[0080] The process is optionally conducted in the presence of a
chain extender which is a polyolol, a polyamino-alcohol, or a
polyamine according to Formula (II) Z(-G).sub.n, in which Z, G, and
n are as defined before, or mixtures thereof, wherein the polyolol,
the polyamino-alcohol, or the polyamine has preferably a molecular
weight of about 56 to about 500 Dalton. Non-limiting examples of
diols are ethylene glycol, diethylene glycol, triethyleneglycol,
1,2-propylene glycol, 1,3-propylene glycol, tetramethylene glycol,
1,5-pentanediol, 1,6-hexandediol, neopenylglycol, and
1,4-butanediol.
[0081] The process for the preparation of the supramolecular
polymer according to this invention can be done by any method known
in the art, for example by simply mixing in a cup, by using a
Banbury-type mixer, by using a Brabender mixer, by using a single
screw extruder, or by using a twin screw extruder. The process is
preferably performed between about 10.degree. C. and about
100.degree. C., more preferably between about 10.degree. C. and
about 90.degree. C., and most preferably between about 20.degree.
C. and about 80.degree. C.
[0082] In one embodiment of the invention no catalyst is added to
the reaction mixture, for example, when isocyanates are reacted
with amines or in some cases where no stoichiometric amounts of
reactants are used. This is preferred when complete absence of
residual catalyst is required for the use of the material, for
example in biomedical applications. In another embodiment of this
invention a catalyst is added to the reaction mixture that promotes
the reactions between the complementary groups. Examples are
catalysts known in the art that promote the reaction between
isocyanates and hydroxyl groups that are derived from tertiary
amines such as 1,4-diazabicyclo[2.2.2]octane (DABCO) or
1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), or derived from
transition metals, such as tin(II)octanoate, dibutyltin(IV)laurate
or zirconium(IV)acetoacetate. Preferably, these catalyst are
tin(IV) or zirconium(IV) compounds. The amount of catalyst is
generally below about 1% by weight, preferably below about 0.2% by
weight and most preferably below about 0.03% by weight of the total
amount of reactants.
[0083] During the preparation of the supramolecular polymer, less
than about 10 weight % of non-reactive organic solvent is present,
preferably less than about 5 weight %, more preferably less than
about 1 weight % and most preferably no non-reactive solvent is
present. These weight percentages are based on the total weight of
the reaction mixture. It is also preferred that the reaction
mixture does not comprise any inorganic solvents such as water.
Non-reactive solvents are preferably selected from non-protic
organic solvents known in the art.
[0084] The supramolecular polymer can be isolated as such, or can
be chopped in pellets, spun in fibers, extruded into films,
directly dissolved in a medium of choice, or transformed or
formulated into whatever form that is desired.
Applications
[0085] The supramolecular polymers according to the invention are
preferably suitable for applications related to coating and
adhesives applications. The present invention therefore also
relates to a coating composition comprising the supramolecular
polymer, and to an adhesive composition comprising the
supramolecular polymer.
EXAMPLES
[0086] The following examples further illustrate the preferred
embodiments of the invention. When not specifically mentioned,
chemicals are obtained from Aldrich.
[0087] Examples 1 to 4 describe functional 4H-units in a liquid
formulation
Example 1
[0088] 2-Acetylbutyrolactone (2 mL) and guanidine carbonate (3.3 g)
were put to reflux in absolute ethanol (20 mL) in the presence of
triethylamine (5.2 mL). The solution became yellow and turbid.
After overnight heating at reflux, the solid was filtered, washed
with ethanol, and suspended in water. The pH was adjusted to a
value of 6-7 with an HCl-solution, and the mixture was stirred for
a while. Filtration, rinsing of the residu with water and ethanol
and subsequent drying of the solid gave the pure 5(2-hydroxy
ethyl)-6-methyl isocytosine. 1H NMR (400 MHz, DMSO-d.sub.6):
.delta. 11.2 (1H), 6.6 (2H), 4.5 (1H), 3.4 (2H), 2.5 (2H), 2.1
(3H).
[0089] The obtained isocytosine (3.21 g) was suspended in
isophorone diisocyanate (IPDI, 26.8 g) and stirred for 16 h at
110.degree. C. under an argon atmosphere, after which it was cooled
to 40.degree. C. resulting in a viscous hazy solution containing a
4H-unit with isocyanate functions formulated in IPDI.
Example 2
[0090] Methylisocytosine (5.2 g) was added to
isophoronediisocyanate (IPDI, 50 mL) and subsequently stirred at
90.degree. C. under an argon atmosphere for 3 days. After cooling
down to 20.degree. C. an isocyanate functional 4H-unit was obtained
formulated in IPDI.
Example 3
[0091] The liquid formulation obtained in Example 2 was
precipitated in heptane. The white gom was collected, heated in 150
mL heptane, cooled on ice, and filtered. The same procedure was
repeated once more with the white residue, resulting in a white
powder formed by the isocyanate functional 4H-unit. 1H NMR (400
MHz, CDCl.sub.3): .delta. 13.1 (1H), 12.0 (1H), 10.1 (1H), 5.9
(1H), 4.1-3.1 (3H), 2.1 (3H), 2.0-0.9 (15H).
[0092] The obtained powder was subsequently suspended in butane
diol (875 mg) and heated to 100.degree. C. for 1 h resulting in a
clear liquid, which was subsequently cooled to 20.degree. C. and
isolated as a clear oil.
Example 4
[0093] Methylisocytosine (0.67 g) was added to methylene
dicyclohexane 4,4-diisocyanate (8.39 g) and subsequently stirred at
110.degree. C. under an argon atmosphere for 16 h. After cooling
down to 40.degree. C. an isocyanate functional 4H-unit was obtained
formulated in methylene dicyclohexane 4,4-diisocyanate.
Example 5
[0094] Hydroxy terminated polyethyleneglycol with a M.sub.n of 600
(4.30 g) was dried at 100.degree. C. in vacuo for 2 hours followed
by the addition of IPDI (741 mg) at 40.degree. C. and 1 drop DBTDL,
and subsequently stirred for 3 h at 40.degree. C. under an argon
atmosphere. To this reaction mixture the 5(2-hydroxy
ethyl)-6-methyl isocytosine (135 mg), obtained in Example 1, was
added and subsequently stirred at 120.degree. C. for 1 h. The
reaction mixture was cooled to 20.degree. C. resulting in a liquid
bis(isocyanate) functional 4H-unit.
[0095] Examples 6 to 9 describe syntheses of the supramolecular
polymers from the liquid formulations of the functional 4H-unit
Example 6
[0096] The isocyanate functional 4H-unit formulated in IPDI from
Example 1 (30.0 g) was mixed with Pripol 2033.TM.
(1,.omega.-bis-hydroxyfunctional C36 compound marketed by Croda)
and 1 drop of DBTDL and stirred at 100.degree. C. for 6 h, followed
by cooling to 70.degree. C. and the addition of 2 mL ethanol. After
1 h the polymer was collected and cooled to 20.degree. C. resulting
in semi-rigid polymer.
Example 7
[0097] The isocyanate functional 4H-unit formulated in methylene
dicyclohexane 4,4-diisocyanate from Example 4 (9.07 g) was mixed
with hydroxy-terminated poly(neopenylglycol-adipate) (13.0 g,
M.sub.n=600) and one drop of DBTDL and stirred for 2 h at
100.degree. C. under an argon atmosphere, followed by the addition
of 1.70 g butanediol and subsequent stirring at 100.degree. C. for
12 h. After which the polymer mass was isolated and cooled to
20.degree. C. resulting in a flexible clear material.
Example 8
[0098] Bis-hydroxy-functional polycaprolactone (PCL, M.sub.n=1250,
1.25 g), predried in vacuo at 100.degree. C., was mixed with IPDI
(1.25 g) at 40.degree. C. followed by the addition of 1 drop DBTDL
and stirred for 3 h under an argon atmosphere resulting in a clear
liquid. This reaction mixture was mixed with the liquid formulation
of Example 3 (0.81 g) comprising the hydroxy-functional 4H-unit.
The liquid mixture was stirred for 5 minutes after which it was
poured into a Teflon mould and heated to 70.degree. C. for 6 h
after which a clear flexible material was obtained.
Example 9
[0099] Hydroxy-terminated poly(ethyleglycol-ran-propyleneglycol)
(2.6 g, M.sub.n=2500), predried in vacuo at 100.degree. C., was
mixed with the liquid formulation of Example 5 comprising the
bis(isocyanate) functional 4H-unit for 5 minutes after which it was
poured into a Teflon mould and heated to 70.degree. C. for 6 h
after which a clear flexible material was obtained.
* * * * *